Robbie Williams to be a fifth judge

The idea is to get the famous acts more involved in the show and the decision making

An X Factor source

The singer, 38, would take turns with other guest performers to become a fifth judge.

Producers also want show boss Simon Cowell, 52, to make a sensational return for the final to judge the panel.

Robbie is in talks to feature as a guest judge on November 4, as well as performing his new single Candy. An X Factor source said: “The idea is to get the famous acts more involved in the show and the decision making.

“They would be there to give their opinion as unbiased judges without having a vested interest in any of the acts.

“Others being approached include Bruno Mars, Pink and Gwen Stefani.” Cowell looks likely to return for the final in December to give his opinions of the finalists and the judges’ song choices.

Our insider added: “Producers know that having him criticising and judging the other judges would be TV gold.”